Beta rebound reduces subsequent movement preparation time by modulating of GABAA inhibition.

Post-movement beta synchronization is an increase of beta power relative to baseline, which commonly used to represent the status quo of the motor system. However, its functional role to the subsequent voluntary motor output and potential electrophysiological significance remain largely unknown. Here, we examined the reaction time of a Go/No-Go task of index finger tapping which performed at the phases of power baseline and post-movement beta synchronization peak induced by index finger abduction movements at different speeds (ballistic/self-paced) in 13 healthy subjects. We found a correlation between the post-movement beta synchronization and reaction time that larger post-movement beta synchronization prolonged the reaction time during Go trials. To probe the electrophysiological significance of post-movement beta synchronization, we assessed intracortical inhibitory measures probably involving GABAB (long-interval intracortical inhibition) and GABAA (short-interval intracortical inhibition) receptors in beta baseline and post-movement beta synchronization peak induced by index finger abduction movements at different speeds. We found that short-interval intracortical inhibition but not long-interval intracortical inhibition increased in post-movement beta synchronization peak compared with that in the power baseline, and was negatively correlated with the change of post-movement beta synchronization peak value. These novel findings indicate that the post-movement beta synchronization is related to forward model updating, with high beta rebound predicting longer time for the preparation of subsequent movement by inhibitory neural pathways of GABAA.

The role of the left dorsolateral prefrontal cortex in conflict control during insomnia disorder.

BACKGROUND: Patients with insomnia are often accompanied by cognitive dysfunction, which seriously affects the quality of life of patients. Repetitive transcranial magnetic stimulation (rTMS) can induce brain neuroplasticity, regulate brain cognitive function and inhibitory control ability. OBJECTIVE: To explore the intervention effect of rTMS on conflict control and sleep quality in patients with insomnia. METHODS: In this single-blind, randomized controlled trial, 39 people with insomnia disorder were randomly divided into real stimulation group and sham stimulation group. The stimulation parameters were stimulation frequency 1 Hz, stimulation intensity 80 % resting motor threshold (RMT), total pulse number 1500 times, time 25 min, and the whole course of treatment lasted 7 days. The Insomnia Severity Index(ISI)、Pittsburgh Sleep Quality Index(PSQI)、Multidimensional Fatigue Inventory(MFI) and Beck Anxiety Inventory(BAI) were assessed at pretest (baseline) and posttest (day 7 after intervention), and the color-word stroop task was used to measure the conflict control ability of the subjects. RESULTS: The sleep quality, correct rate and reaction time of the posttest in the real stimulus group were higher than those in the pretest. However, there was no significant difference between the pretest and posttest in the sham stimulation group. CONCLUSIONS: rTMS stimulation of the left dorsolateral prefrontal cortex (LDLPFC) in patients with insomnia can significantly improve the conflict control ability and sleep quality of patients with insomnia.

Altered electrophysiology mechanism related to inhibitory control in adults with insomnia.

Background: Insomnia disorder (ID), one of the most common psychophysiological disorders, can cause a serious burden on the individual's work and academic performance. Cognitive dysfunction often exists in patients with insomnia, which negatively affects their living quality. Inhibitory control (IC), as a vital cognitive function, allows individuals to suppress attention, behavior, or thoughts that are irrelevant to the task, so as to effectively adapt to the current goal. The earlier studies on the inhibitory control of insomnia patients predominantly used subjective scales for evaluation and that can have drawbacks because they don't provide an objective assessment. Methods: In order to investigate the inhibitory control function of insomniacs, this research subdivides inhibitory control into response inhibition and conflict inhibition. The response inhibition and conflict inhibition capacities of insomniacs were evaluated using the two-choice oddball task and the color-word stroop task, and accordingly the association between insomnia disorder and inhibitory control capacity as well as its cognitive neural mechanism was able to be examined. Results: Behavioral results finding, insomniacs conducted the two-choice oddball test and the color-word stroop task with lower accuracy and slower reaction times when compared to healthy sleepers. ERP results finding, when performing the two-choice oddball task, the P3 amplitude of the insomniacs was significantly lower than that of healthy sleepers while there was no significant difference between the two groups' N2 amplitudes. At the same time, when completing the color-word stroop task, the insomniacs' N450 amplitude was significantly lower than that of healthy sleepers. Discussion: The above findings suggest that in response inhibition tasks, insomniacs may have weaker motor inhibition abilities, and similarly perform weaker conflict monitoring abilities in conflict inhibition tasks, which indicates that insomniacs' inhibitory control is impaired compared to that of healthy sleepers. This study thus relates to the finding at the electrophysiological level that there is a certain correlation between insomnia and a decline in inhibitory control ability, which may suggest that improving inhibitory control function in patients with insomnia is a clinically significant and worthwhile area of adjuvant treatment.

Maxillary gingival neurolemmoma: a case report and literature review.

OBJECTIVE: To explore and summarize the clinical features, differential diagnosis and treatment of the oral maxillofacial schwandoma. CASE PRESENTATION: This is a report of a case of a 46-year-old female patients with neurolemmoma in the maxillary gingiva. The clinical features, pathological features, differential diagnosis and treatment were analyzed. Literature review was conducted in search of domestic and overseas journal full-text database from 1986 ~ 2017. 39 reports on the oral and maxillofacial Neurolemmoma from 1986 to 2017 in the database of China hospital knowledge database and the PubMed database, there were 405 patients. There were 23 cases of gingival mucosa, 17 in foreign literature and only 6 in the domestic literature. CONCLUSIONS: The incidence of gingival Neurolemmoma is extremely low, the predilection age is similar to other parts, it is middle-aged and young, and there is no obvious gender tendency. About 25-45% of schwannomas are found in the head and neck, and rarely in the mouth (only 1%). The most common internal location of the mouth is the tongue, followed by the floor of the mouth, buccal mucosa, palate, gums, and lips. Schwannomas are slow-growing benign tumors that are rare in the gums. Gingival schwannoma is usually a single occurrence, and the clinical manifestations are mostly painless gum mass, tooth loosening and displacement, without peripheral bone changes and regional lymph node metastasis. It is difficult to diagnose this tumor according to clinical manifestations, and pathological diagnosis is still the basis for the diagnosis of gingival schwannoma. So far, surgical resection is the preferred treatment for this disease, and the prognosis is good.

Insulin-like growth factor-1 inhibits apoptosis of rat gastric smooth muscle cells under high glucose condition via adenosine monophosphate-activated protein kinase (AMPK) pathway.

INTRODUCTION: Diabetic gastroparesis (DGP) is a common chronic complication of diabetes characterized by decreased gastric motility, and an effective number of gastric smooth muscle cells (GSMCs) ensures gastric motility. A previous study documented that apoptosis was present in gastric smooth muscles in rats with DGP and adenosine monophosphate-activated protein kinase (AMPK) was an important factor of apoptosis of rat GSMCs cultured under high glucose conditions. This study aimed to explore the effect of insulin-like growth factor-1 (IGF-1) on apoptosis of high glucose cultured rat GSMCs after silencing of AMPK and elucidate the underlying mechanism. MATERIAL AND METHODS: A total of 120 rats were divided into normal control (NC, n = 20), diabetic gastroparesis (DGP, n = 50) and DGP + IGF-1 (n = 50) groups. After establishing the rat model of DGP, rats in the DGP+IGF-1 group received an intraperitoneal injection of IGF-1 at a dose of 1.5 µg/kg/d for 10 weeks. The level of AMPK activity, liver kinase B1 (LKB1) activity, and calcium/calmodulin-dependent protein kinase b (CaMKKb) expression in rat gastric smooth muscle tissues was detected by Western blot analysis. Apoptosis in rat gastric smooth muscle tissues was detected by TUNEL assay. We also cultured rat GSMCs in vitro under high glucose (HG) condition (35 mM), incubated cells with IGF-1, and silenced AMPK with siRNA. The cells were divided into HG, HG + IGF-1, HG + siRNA, and HG + siRNA + IGF-1 groups. The apoptosis rates of rat GSMCs after silencing AMPK were detected by TUNEL assay and flow cytometry, and apoptosis-related protein expression in rat GSMCs was detected by Western blot. RESULTS: IGF-1 decreased LKB1 activity, CaMKKb expression, AMPK activity, and inhibited apoptosis in rat gastric smooth muscle tissues. Compared with rat GSMCs cultured in vitro under HG conditions, apoptosis rates were reduced after treatment with IGF-1 and AMPK silencing (both p < 0.01). Apoptosis rates were higher in the HG + siRNA group compared with the HG + IGF-1 group (p < 0.05). IGF-1 down-regulated the expression of calcium/calmodulin-dependent kinase II (CaMKII) and p53, up-regulated the expression of p21, PLC-b3, PI3K p110 Ser1070, and the activities of Akt, p70S6K, mTORC1, and mTORC2. IGF-1 also up-regulated Bcl-2 expression and down-regulated the expression of BAX and Caspase-3. CONCLUSIONS: IGF-1 can inhibit the apoptosis of rat GSMCs under high glucose conditions, its mechanism may be related to the regulation of expression and activity of p53, PI3K, TSC-2, Akt, mTOR, 4E-BP1, p70S6K, p21, CaMKII, and PLC-b3 in rat GSMCs acting through AMPK pathway.

Analysis of Factors Related to Distal Proximal Caries on the Distal Surface of the Mandibular Second Molar Induced by an Impacted Mandibular Third Molar.

OBJECTIVE: To analyze the factors related to distal proximal caries of the mandibular second molar (MSM) induced by an impacted mandibular third molar (MTM). METHODS: A total 500 panoramic radiographs of patients with impacted MTMs who were treated in the Department of Stomatology of the Affiliated Hospital of Yanbian University between October 2017 and October 2019 were selected. Descriptive and bivariate analyses were conducted, and the diagnosis of caries in the MSM and the position of the MTM were evaluated. RESULTS: The posterior margin space of the MSM was larger in males (13.5 mm) than females (11.1 mm, P < 0.001) and correlated with the MTM's impacted depth and eruption degree (P < 0.001). The prevalence of distal proximal caries of the MSM was 37.6%, and a χ 2 test showed that age, impacted depth, impacted direction, impacted angle, degree of occurrence, and CEJ distance were correlated with caries in the distal adjacent surface of the MSM (P < 0.001). Logistic multivariate analysis showed that the impacted depth was at position A or B, the impacted direction was mesioangular, and the impacted angle was <80°. Distal adjacent caries of MSMs were prone to occur when entirely or partially emergent. CEJ distance was not an independent factor for caries. The severity of caries in an MSM's distal adjacent surface had statistical significance on the impacted depth and impacted angle (P < 0.001). CONCLUSION: The posterior margin space of the MSM influences the impacted condition of the MTM. Preventive extraction can be considered if the impacted angle is <80°, especially in the case of a fully or partially emergent MTM at position A or B and mesioangular impacted areas.

Movement speed effects on beta-band oscillations in sensorimotor cortex during voluntary activity.

Beta-band oscillations are a dominant feature in the sensorimotor system, which includes movement-related beta desynchronization (MRBD) during the preparation and execution phases of movement and postmovement beta synchronization (PMBS) on movement cessation. Many studies have linked this rhythm to motor functions. However, its associations to the movement speed are still unclear. We make a hypothesis that PMBS will be modulated with increasing of movement speeds. We assessed the MRBD and PMBS during isotonic slower self-paced and ballistic movements with 15 healthy subjects. Furthermore, we conduct an additional control experiment with the isometric contraction with two levels of forces to match those in the isotonic slower self-paced and ballistic movements separately. We found that the amplitude of PMBS but not MRBD in motor cortex is modulated by the speed during voluntary movement. PMBS was positively correlated with movement speed and acceleration through the partial correlation analysis. However, there were no changes in the PMBS and MRBD during the isometric contraction with two levels of forces. These results demonstrate a different function of PMBS and MRBD to the movement speed during voluntary activity and suggest that the movement speed would affect the amplitude of PMBS.NEW & NOTEWORTHY Beta-band oscillations are a dominant feature in the sensorimotor system that associate to the motor function. We found that the movement-related postmovement beta synchronization (PMBS) over the contralateral sensorimotor cortex was positively correlated with the speed of a voluntary movement, but the movement-related beta desynchronization (MRBD) was not. Our results show a differential response of the PMBS and MRBD to the movement speed during voluntary movement.

Alpha Frequency Intervention by Electrical Stimulation to Improve Performance in Mu-Based BCI.

The accuracy of brain-computer interfaces (BCIs) is important for effective communication and control. The mu-based BCI is one of the most widely used systems, of which the related methods to improve users' accuracy are still poorly studied, especially for the BCI illiteracy. Here, we examined a way to enhance mu-based BCI performance by electrically stimulating the ulnar nerve of the contralateral wrist at the alpha frequency (10 Hz) during left- and right-hand motor imagination in two BCI groups (literate and illiterate). We demonstrate that this alpha frequency intervention enhances the classification accuracy between left- and right-hand motor imagery from 66.41% to 81.57% immediately after intervention and to 75.28% two days after intervention in the BCI illiteracy group, while classification accuracy improves from 82.12% to 91.84% immediately after intervention and to 89.03% two days after intervention in the BCI literacy group. However, the classification accuracy did not change before and after the sham intervention (no electrical stimulation). Furthermore, the ERD on the primary sensorimotor cortex during left- or right-hand motor imagery tasks was more visible at the mu-rhythm (8-13 Hz) after alpha frequency intervention. Alpha frequency intervention increases the mu-rhythm power difference between left- and right-hand motor imagery tasks. These results provide evidence that alpha frequency intervention is an effective way to improve BCI performance by regulating the mu-rhythm which might provide a way to reduce BCI illiteracy.

Mechanism of AMPK-mediated apoptosis of rat gastric smooth muscle cells under high glucose condition.

To observe changes in AMP-activated protein kinase (AMPK) activity and phosphorylation changes in AMPK signaling pathway in gastric smooth muscle cells of rats with diabetic gastroparesis (DGP), investigate the effect of AMPK on apoptosis and explore the underlying mechanism. After establishing rat model of DGP, rats were divided into normal control (NC) and DGP groups. The phosphorylation changes in AMPK pathway were detected by AMPK Signaling Phospho-Antibody Array, and the apoptosis-related proteins were determined. Rat gastric smooth muscle cells were cultured in vitro under different glucose conditions, and divided into normal and high glucose groups. The AMPK activity and intracellular Ca2+ changes in cells were observed. After AMPK silencing, cells were divided into high glucose-24h, high glucose-48h and high glucose-48h+siRNA groups. Changes in expression of apoptosis-related proteins were observed. AMPK activity and apoptosis rates were both increased in gastric smooth muscle tissues in DGP rats (P<0.05, P<0.001, respectively). A total of 14 apoptosis-related differentially phosphorylated proteins were identified. Under high-glucose condition, AMPK activity and intracellular Ca2+ concentrations in rat gastric smooth muscle cells were increased (both P<0.05). After AMPK silencing, p53 expression was decreased, Akt and p70 S6 ribosomal protein kinase (p70S6K) activities were were increased, Bcl-2 expression was increased, CaMKII activity was decreased in the high glucose-48h group. Under high-glucose condition, activated AMPK can directly or indirectly promote cells apoptosis by regulating the expression and activity of p53, Akt, p70S6K, Protein kinase A (PKA), Phospholipidol C (PLC)-ß3, CaMKII, CaMKIV and eukaryotic translation initiation factor 4E binding protein1 (4E-BP1) in rat gastric smooth muscle cells.

Enhancing Mu-based BCI Performance with Rhythmic Electrical Stimulation at Alpha Frequency.

The accuracy of brain-computer interfaces (BCIs) is important for effective communication and control. The mu-based BCI is one of the widely used systems, of which the related methods to improve users' accuracy is still poorly studied. Here, we examined the way to enhance the mu-based BCI performance by rhythmic electrical stimulation on the ulnar nerve at the contralateral wrist at the alpha frequency (10 Hz) during the left-and right-hand motor imagery. Time-frequency analysis, spectral analysis, and discriminant analysis were performed on the electroencephalograph (EEG) data before and after the intervention of electrical stimulation in 9 healthy subjects. We found that the ERD/S on the somatosensory and motor cortex during left-or right-hand imagination was more obvious at the mu rhythm after intervention. Furthermore, average classification accuracy between left-and right-hand imagery significantly increased from 78.43% to 88.17% after intervention, suggesting that the electrical stimulation at alpha frequency effectively regulates the brain's mu rhythm and enhances the discriminability of the left-hand and right-hand imagination tasks. These results provide evidence that the electrical stimulation at the alpha frequency is an effective way to improve the mu-based BCI performance.

Study on Feature Selection Methods for Depression Detection Using Three-Electrode EEG Data.

The early diagnosis of depression is important to the treatment of this condition, whereas a timely diagnosis can reduce the incidence of mortality caused in patients with depression. In the present study, we collected the EEG signals of Fp2, Fpz and Fp1, compared with 128 channels EEG, a simpler test (3 channels EEG) can make diagnosis more accessible and widespread, researchers can perform more tests on more patients given the same amount of time and money. The difference between the depressed and the non-depressed patients was explored by the linear and non-linear characteristics of these EEG signals. A total of 152 patients with depression and 113 healthy subjects participated in the study. In the current report, the linear features were as follows: peak, variance, inclination, kurtosis and Hjorth parameter. The nonlinear features included C0 complexity, correlation dimension, Shannon entropy, Kolmogorov entropy and power spectrum entropy. With regard to the aforementioned characteristics, the present report utilized four feature selection algorithms, namely WrapperSubsetEval, CorrelationAttributeEval, GainRatioAttributeEval, and PrincipalComponents and five classification algorithms that included Support Vector Machine, K-Nearest Neighbor, Decision Tree, Logistics Regression and Random Forest. The experimental results indicated that the WrapperSubsetEval of the wrapper class exhibited higher performance compared with the other three feature selection algorithms on each classifier, whereas the highest classification accuracy was 76.4. It is suggested that this analysis may be a complementary tool to aid psychiatrists in the diagnosis of depressed patients.

Kinetics and mechanisms of pH-dependent selenite removal by zero valent iron.

The kinetics of Se(IV) removal by zero valent iron (ZVI) open to the air as a function of pH and the involved mechanisms were investigated in this study. The specific rate constants of Se(IV) removal by ZVI decreased from 92.87 to 6.87 L h(-1) m(-2) as pH increased from 4.0 to 7.0. The positive correlation between the removal rate of Se(IV) and the generation rate of Fe(II) and the depression of Se(IV) removal in the presence of 1,10-phenanthroline indicated that both ZVI and adsorbed Fe(II) on ZVI surface contributed to the reductive removal of Se(IV). The soft X-ray STXM measurement confirmed the adsorption of Fe(II) on the surface of ZVI and freshly formed ferric (hydr)oxides. Se(IV) was removed by adsorption followed by reduction to Se(0) on ZVI surface at pH 4.0-7.0, as revealed by XANES spectra. A core-shell structure was observed when ZVI reacted with Se(IV)-containing solution for 3 h at pH 6.0. Se(IV) was reduced to Se(0) and co-precipitated with the freshly formed Fe(III), forming the shell surrounding the iron core. After reaction for 24 h, the generated Se(0) was surrounded by multiple layers of Fe(III) oxides/hydroxides. SEM images and XRD patterns revealed that the corrosion products of ZVI at pH 6.0 transformed from amorphous iron hydroxides to lepidocrocite (γ-FeOOH) as reaction proceeded. The final corrosion products of ZVI contained both lepidocrocite and goethite at pH 5.0 while they were X-ray amorphous at pH 4.0 and 7.0.